Make counting ALL untracked files optional

[root42]

I am working via sshfs on a large repository which mixes source files with build artifacts. Hence I get potentially lots and lots of untracked files. Sometimes the git status takes 5 minutes to complete, if the connection is bad. I also do not need this information.

So I made the parameter for git status --untracked-files configurable. There is now a new environment variable, called GIT_SHOW_UNTRACKED_FILES, which if set is passed to git status. If it is not set, default behaviour of "all" will apply. Setting it to "no" or "normal" will speed things up a lot.

[magicmonty]

Thanks, could you please add a remark in the README for documentation to?

[root42]

Done.

[magicmonty]

Thanks